Cell surface glycoproteins have been shown to undergo qualitative and quantitative changes during cellular transformation and during the growth phases of cells in culture. They have been implicated as being involved in cellular adhesion, cellular migration and aggregation and in cell-cell communication. During the coming year, we will continue our studies on the biosynthesis of cell surface and soluble glycoproteins. Our research involves the solubilization, purification and characterization of enzymes that catalyze the incorporation of sugars into the carbohydrate side chains of glycoproteins. We will also continue to isolate, purify and characterize oligosaccharide-lipids that are intermediates in the biosynthetic pathway. The oligosaccharide-lipids will be isolated in sufficient quantities for use as acceptors during studies on the glycosyltransferases. Our major emphasis, however, will be to continue studies on the reconstitution of the purified enzymes with phospholipids. Our results suggest that at least two of the enzymes in the biosynthetic pathway are optimally active in the presence of non-bilayer phospholipid phases. Our goal is to determine whether other enzymes in the pathway require non-bilayer phospholipid phases for activity and if these unique phases are involved in vitro in glycoprotein biosynthesis.